Multi-bearing acetabular prosthesis

ABSTRACT

A prosthesis to replace a portion of the anatomy, such as the acetabulum, can include a first portion. A second prosthesis portion can be positioned relative to the shell to provide the bearing surface to articulate with a femoral head prosthesis or femoral head. The second prosthesis portion can include a connection portion to engage a connection portion in the shell.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/624,142 filed on Nov. 23, 2009, which claims the benefit of U.S.Provisional Application No. 61/117,249, filed on Nov. 24, 2008. Theentire disclosures of the above applications are incorporated herein byreference.

FIELD

The present disclosure relates to a modular prosthesis, particularly toan acetabular prosthesis including a plurality of liners operable tointerconnect with a single acetabular shell.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

Articulating regions of the anatomy can include areas where two bonesections move relative to one another. For example, an acetabulum canprovide a region for articulation with a femoral head. The articulatingregion, however, can become injured or worn, but it can be replaced withvarious prostheses. Prostheses can replace the acetabulum, the femoralhead, various other portions of the femur, or combinations thereof. Thereplacement of both the acetabulum and the femoral head is generallyreferred to as a total joint replacement.

The total joint replacement of the acetabulum and the femoral headrequires a bearing or articulating surface for both the femoral head andthe acetabulum. The articulating surfaces are generally positionedrelative to the various portions of the remaining natural anatomy in asubstantially fixed manner. Materials must be selected for the bearingsurfaces for various purposes.

SUMMARY

A prosthesis to replace a portion of the anatomy, such as the acetabulumcan include a first portion, such as a cup or shell, that can be fixedto, for example, the pelvis. The pelvis can be prepared in anyappropriate manner to receive fixation of the cup. The prosthesis caninclude a second portion, such as a liner or bearing, that can bepositioned relative to the shell to provide a bearing surface toarticulate with a femoral head prosthesis. It will be understood,however, that a selected bearing component can be provided to articulateor provide a bearing surface relative to a natural femoral head.

The prosthesis system can include a single shell that can beinterconnected with two or more bearing members. The bearing members caninclude various characteristics or material selections, such as apolymer bearing and a metal bearing. The polymer bearing can provide arelatively soft surface for a member to bear against. The metal bearing,relative to the polymer bearing, can provide a substantially hard ortough surface to bear against. The different bearing materials can alsoinclude different connection portions to interconnect with the shell.The shell can include connecting regions to connect with the multiplebearing members.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1A is a perspective exploded view of an acetabular assembly,according to various embodiments;

FIG. 1B is a cross-sectional view of a first liner positioned in a shellof the assembly of FIG. 1A, according to various embodiments;

FIG. 1C is a cross-sectional view of a second liner positioned in ashell of the assembly of FIG. 1A, according to various embodiments;

FIG. 2A is a perspective exploded view of an acetabular assembly,according to various embodiments;

FIG. 2B is a cross-sectional view of a first liner positioned in a shellof the assembly of FIG. 2A, according to various embodiments;

FIG. 2C is a cross-sectional view of a second liner positioned in ashell of the assembly of FIG. 2A, according to various embodiments;

FIG. 3A is a perspective exploded view of an acetabular assembly,according to various embodiments;

FIG. 3B is a cross-sectional view of a first liner positioned in a shellof the assembly of FIG. 3A, according to various embodiments;

FIG. 3C is a cross-sectional view of a second liner positioned in ashell similar to the assembly of FIG. 3A, according to variousembodiments;

FIG. 3D is a cross-sectional view of a second liner positioned in ashell of the assembly of FIG. 3A, according to various embodiments;

FIG. 4A is a perspective exploded view of an acetabular assembly,according to various embodiments;

FIG. 4B is a top plan view of a liner inserted in a shell according tovarious embodiments;

FIG. 4C is a cross-sectional view of a first liner positioned in a shellof the assembly of FIG. 4A, according to various embodiments;

FIG. 4D is a detailed view of a liner and shell, according to variousembodiments;

FIG. 4E is a detailed view of a liner and shell, according to variousembodiments;

FIG. 5A is a perspective exploded view of an acetabular assembly,according to various embodiments;

FIG. 5B is a cross-sectional view of a shell and liner connected,according to various embodiments;

FIG. 5C is a cross-sectional view of a shell and insertion assemblyaccording to various embodiments;

FIG. 6A is a perspective exploded view of an acetabular assembly,according to various embodiments;

FIG. 6B is a cross-sectional view of a shell and a positioninginstrument;

FIG. 6C is a cross-sectional view of a shell and the liner connected;and

FIG. 7 is an environmental view of an acetabular assembly positionedrelative to an acetabulum of a patient.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses. Althoughvarious embodiments are discussed below, including exemplary materials,it will be understood that any appropriate materials or combinations maybe selected for use with the assemblies.

With reference to FIGS. 1A and 7, in a selected procedure, such as animplantation of an acetabular prosthesis implantation procedure, anacetabular prosthesis, according to various embodiments, can bepositioned into an acetabulum 18. According to various embodiments, anacetabulum prosthesis assembly can include a multiple-bearing acetabularassembly 20 including a shell prosthesis 22 into which a first liner 24and a second liner 26 can be positioned with or without a connectingmember 28. The first liner 24 and the second liner 26 can be made of thesame or different materials and different sizes, but can be provided tointerconnect with the single shell 22, according to various embodiments.

The first liner 24 can be formed of a substantially or relatively hardor rigid material, such as a ceramic material (e.g. the ceramic Biolox®Delta sold by CeramTec, having a place of business in South Carolina),metals (e.g. titanium, titanium alloys, stainless steel alloys, cobaltchromium alloys), and other appropriate metals or rigid polymers, suchas polyetheretherketone (PEEK), for example. The rigid material of thefirst liner 24 can be any appropriate biocompatible rigid material thatcan provide a bearing surface for a selected portion, such as a femoralhead implant or a natural femoral head 34, as illustrated in FIG. 7.With reference to FIGS. 1A, 1B, and 7, the first liner 24 can include aninternal bearing surface 30 that is operable to bear on or articulatewith a femoral head implant 32 a, 32 b or a natural femoral head 34. Thebearing surface 30 can be provided in any appropriate manner, such as ahighly polished or substantially smooth surface for articulation with aselected member.

The first liner 24 can also include an exterior surface 36 which can beprovided to cooperate with an interior surface 38 of the shell 22. Theinterior surface 38 of the shell 22 can define a void generally in anarea between a line Al and the rim 70 of the shell 22. The void caninclude a generally concave shape depicted in various embodiments. Theinterior surface 38 of the shell 22 can be provided in any appropriatemanner, such as substantially highly polished or substantially smooth.The interior surface 38 can contact the exterior surface 36 of the firstliner 24 substantially tightly or with any appropriate gaps. Forexample, the interior surface 38 can be provided to not contact theexterior surface 36 to assist in providing a select interaction oftapers, as discussed herein. Alternatively, the interior surface 38 cancontact the exterior surface completely or in part, according to variousembodiments.

The first liner 24 can be interconnected or fixedly positioned relativeto the shell 22 via the interconnection of a female taper 40 definedsubstantially near a center and/or apex of the shell 22. The femaletaper 40 can be defined by a female taper wall 42. The female taper wall42 can define part of or be positioned near an apical hole or passage43. The taper wall 42 can be formed in the shell 22 in any appropriatemanner, such as casting, machining, etching, etc. The female wall taper42 can also be provided in any appropriate configuration such assubstantially smooth or rough for connection with a male taper 44defined by the first liner 24.

The male taper 44 can be formed substantially integrally or as a singleportion with the first liner 24 and defined by a male taper wall 46. Themale taper 44 need not be a separate portion that is interconnected withthe exterior surface 36 of the first liner 24, but can define a portionof the exterior surface of the first liner 24. The male taper wall 46can include an appropriate angle relative to a central or concentricaxis of the first liner 24.

The angle of the male taper wall 46 can be substantially identical orsimilar to an angle of the female taper wall 42. The tapers 40, 44 caninclude selected angles such as about 1 degree to about 45 degrees. Theangles can allow the male taper 44 to engage the female taper 40 in asubstantially locked or connected manner, such as with a Morse taper.The interconnection of the tapers 40, 44 can allow a fixation of thefirst liner 24 into the shell 22 at a selected time.

The female taper 40 can also assist in aligning the first liner 24during implantation of the first liner 24 into the shell 22.Furthermore, the female taper 40 can be positioned near the throughboreor passage 43 to assist with implantation of the shell 22. The passage43 can be used with an implantation tool to assist in positioning theshell 22 in a selected location. Also, an apical plug or other membercan be positioned in the apical hole 43, if selected. The shell 22,according to various embodiments, can also include other bores, externalprojections, etc., to assist in positioning and fixing the shell 22 tothe anatomy 500. Exemplary implantation tool systems include apical holeinserters, sold by Biomet, Inc. of Warsaw, Ind., USA.

The shell 22 can also be provided in different sizes or configurations.For example, a diameter or height of the shell 22 can be altered basedupon different portions that articulate with the first liner 24, thesize of the patient, or other appropriate considerations. The shell 22defined by a shell wall portion or member 22 a can also be provided inmultiple thicknesses.

A first thickness 54 can be provided which can be less than a secondthickness 56. The first and second thicknesses 54, 56 can also alter orchange the dimensions of the female taper 40. The male taper 44 canlikewise include a first thickness 58 or a second thickness 60. Thefirst and second thicknesses 58, 60 of the male taper 44 can be formedto be substantially complementary or operably complement the femaletaper thicknesses 54, 56. It will be understood, however, that a systemor kit of the shells 22 and the first liners 24 can include multipleliners of multiple sizes, including two or more thicknesses of thefemale taper 40 or the male taper 44.

Different sizes can be provided for different reasons. For example, thedifferent sizes of the shell 22 with different sizes of the first liner24 can include different thicknesses that require different thicknessesof the female and male tapers 40, 44. The thickness of the tapers 40, 44can be selected for specific or selected applications. For example, athicker taper, such as the thicker female taper 56 and the thicker maletaper 60, can be provided for a substantially stronger or longer wearconnection. A thicker taper can be provided in a substantially youngeror more active patient. Other reasons may also exist for using differentthicknesses. For example, if a patient has a deeper or substantiallyworn acetabulum, a deeper or thicker taper may fit better in thatpatient.

As is clearly illustrated in FIGS. 1A and 1B, the female taper 40defined by the shell 22 can be positioned at a location of the shell 22that is substantially a distance away, such as a maximum distance away,from a rim 70 of the shell 22. The rim 70 generally defines a portion ofan exterior surface of the shell 22. Positioned near the rim 70 can be agroove or connection area 72. The first groove 72 can receive orinterconnect with the connecting member 28. The connecting member 28 cancooperate with a second groove 74 of the second liner 26 to assist ininterconnecting the second liner 26 with the shell 22. The first groove72 defined by the shell 22 can be positioned substantially near the rim70 of the shell 22. This can position the first groove 72 at a distancefrom the apical hole or passage 43. The grooves 72, 74 can be sized inany appropriate manner to receive or cooperate with the connectingmember 28, such as in the Ringlac® acetabular implant sold by Biomet,Inc. of Warsaw, Ind., USA.

The second liner 26 can be formed of any appropriate materials, such aspolymers including ultra-high molecular weight polyethylene (UHMWPE) orpolyetheretherketone (PEEK). Any appropriate material can be used toform the second liner 26, but the second liner 26 may generally besubstantially softer or less rigid than the first liner 24. Continuingto refer to FIG. 1A and additionally to FIG. 1C, the second liner 26 caninterconnect or be positioned relative to the shell 22 with theconnecting member 28. The second liner 26, the connecting member 28, andthe shell 22 can be provided as three separate pieces or the connectingmember 28 can be pre-fit into either of the grooves 72, 74 defined bythe second liner 26 or shell 22. This can allow a user, such as asurgeon, to press the second liner 26 into the shell 22 and theconnecting member 28 can compress or expand relative to the opening orvoid 76 to allow it to pass over a portion of the shell 22 or the secondliner 26 and expand into the grooves 72, 74. The connecting member 28includes a width 78 great enough to engage both the first groove 72 andthe second groove 74 in the respective shell 22 and the second liner 26.Therefore, the connecting member 28 can fixedly hold the second liner 26relative to the shell 22, at least in an axial position.

The second liner 26 can also include an anti-rotation system includingan anti-rotation tab 80 and associated depression 81 at an upper rim 27of the second liner 26. The rim 70 of the shell 22 can also includecomplementary anti-rotation projections 82 and associated depressions 83to assist in minimizing or eliminating rotation of the second liner 26relative to the shell 22 after implantation. The anti-rotationprojections 82 can be positioned exterior to the internal surface orcavity 38 of the shell 22.

The second liner 26 can also include any appropriate size forpositioning in the shell 22. The second liner 26 can be selected toinclude an articulation or internal surface 86 for articulation relativeto the femoral implant 32 a, 32 b or a natural femoral head 34. Anexternal surface 88 of the second liner 26 can also engage the internalsurface 38 of the shell 22 in an appropriate manner, such as asubstantially fixed or non-moving manner.

The second liner 26 can also include an optional projection 89. Theprojection 89 can extend from the exterior surface 88 of the secondliner 26 and be positioned in or engage the female taper 40. Accordingto various embodiments, the projection 89 does not lock with the femaletaper 40. The projection 89 can be provided, according to variousembodiments, only for alignment of the second liner 26. Alternatively,the projection 89 may lock with the female taper 40.

Briefly, the provision of the first liner 24 and the second liner 26allows for a pre-operative or intra-operative selection of liners forpositioning within the shell 22. In addition, or alternatively, theprovision of the first liner 24 and the second liner 26 that can engagethe shell 22 can minimize the number of parts for a procedure. Forexample, rather than requiring a first shell to engage the first liner24 and a second shell to engage the second liner 26, only the singleshell 22 is needed to engage both the first liner 24 and the secondliner 26.

According to various embodiments, a multiple-liner acetabular prosthesisassembly 200 is illustrated in FIGS. 2A-2C. The acetabular prosthesisassembly 200 can include a single shell 202 that can be interconnectedwith a first bearing or liner 204. The first liner 204 can be formed ofa substantially hard or rigid material, including ceramic or metalalloys, similar to the first liner 24 discussed above. A second liner206 can include or be interconnected with a shell 202 with a connectingmember 208. The second liner 206 can be formed of a less rigid or softermaterial, including the polymers discussed above in relation to thesecond liner 26. The first liner 204 or the second liner 206 can beinterconnected with the single shell 202, similar to the provision ofthe first liner 24 and the second liner 26 that can also beinterconnected with the single shell 22. The first liner 204 and thesecond liner 206, however, can include different connection portions forinterconnecting with the single shell 202.

The first liner 204 can include a rim 210 defined at an exterior edge ofthe liner 204. Positioned below the rim 210 of the first liner 204 is ataper wall 212 that defines a substantially straight wall portionrelative to an exterior wall 214 of the remainder of the first liner204.

The straight wall portion of the taper wall 212 can include a taperrelative to a substantially central or concentric axis 204 a defined bythe first liner 204. The taper angle of the taper wall 212 can be anyappropriate taper angle, including those that are similar to the anglesof the taper wall 46. For example, the taper connection can define aMorse taper with a female or internal taper 216 defined by the shell202. The tapers 212, 216 can be provided substantially complementary ormating such that the two tapers 212, 216 can be used to lock the firstliner 204 relative to the shell 202. The substantially rigid material ofthe first liner 204 can be used to ensure a rigid connection of the twotapers 212, 216.

As discussed above, the first liner 204 can be positioned into the shell202 and fixed in place by positioning the two tapers 212, 216 relativeto one another. The taper connection can offer a substantially fixedposition of the first liner 204 in both an axial position and rotationalposition relative to the shell 202. Also, the tapers 212, 216 caninclude any appropriate heights or dimensions. Further, the first liner204 can include a plurality of liners each measuring different heightsto allow selection of an amount of contact area between the male taper212 and the female taper 216. Each of a plurality of the first liners204 can also include different dimensions, such as an internal diameter,an external diameter, etc.

The shell 202 can also include an apical or proximal bore or opening220. The opening 220 in the shell 202 can be used similarly to theapical hole 43 in the shell 22. For example, an implantation instrumentcan be used to engage the opening 220 to implant the shell 202 relativeto the acetabulum 18. Further, the opening 220 can include an internalor first groove 222 that can engage or receive the connecting member208. The second shell 206 can include a second groove 224 to alsopartially or completely receive or engage the connecting member 208.Similar to the connecting member 28, the connecting member 208 caninclude a recess or opening to allow for a deformation of the connectingmember 208. Therefore, as a user, such as a surgeon, presses the secondliner 206 into the opening 220, the connecting member 208 can firstcompress and then rebound to engage both the first groove 222 and thesecond groove 224 to substantially hold the second liner 206 axiallyrelative to the shell 202. Alternatively, the connecting member 208 canalso first be positioned in the first groove 222 or placed between theliner 206 and shell 202 prior to a surgeon or other user pressing theliner 206 into the shell 202.

The second liner 206 can also include an anti-rotation system includinganti-rotation projections 230 and recesses 231. The shell 202 at a rimor upper portion 232 can include a complementary anti-rotation systemincluding recesses 233 and projections 235. The anti-rotation system canresist rotation of the second liner 206 . The second liner 206 can alsobe held axially in the shell 202 with the locking system discussedabove.

The second liner 206 can also be formed in differing dimensions, forexample, thicknesses and diameters, to be interconnected with the shell202. The second liner 206 can be provided in differing sizes for reasonssimilar to those disclosed above, including patient's specifications,implant selections, and the like. Also, a kit of a plurality of thefirst liners 204 and second liners 206 can be provided with varyingcharacteristics.

Nevertheless, according to various embodiments, the shell 202 canprovide for a connection between different liners, such as the firstliner 204 and the second liner 206. The connection areas defined by theshell 202 can be provided at substantially distant or extremely distantpositions relative to each other. The female taper 216 can be positionedsubstantially near the rim 232 while the groove 222 can be positionedsubstantially near or in the apical opening 220. Therefore, the twoconnection systems can be provided substantially independent of oneanother, but still allowing for interconnection of multiple connectingportions. The two connection systems, however, can also be provided toboth engage and connect to a single liner, as discussed herein. Inaddition, for reasons similar to the acetabular system 20, the multiplebearings can be interconnected with a single shell 202 for variousreasons.

With reference to FIGS. 3A-3C, a multiple liner acetabular system 300,according to various embodiments, is illustrated. The acetabularassembly 300 can include a single shell 302, a first liner or bearingmember 304 and a second liner or bearing member 306. The shell 302 canbe interconnected with the liners 304, 306.

Briefly, the first liner 304 can be substantially similar to the firstliner 204 of the acetabular assembly 200. The first liner 304 caninclude a male taper portion 310 at or near a rim 312 of the first liner304. An exterior portion 316 of the first liner 304 can be provided toengage or be positioned within the shell 302 in any appropriate manner.An internal surface 318 of the first liner 304 can be provided toarticulate with any appropriate portion, such as a femoral implant 32 a,32 b or a femoral head 34. In addition, similar to the shell 202 of theacetabular assembly 200, the shell 302 includes a female taper 320 at ornear a rim 322 of the shell 302. The female taper 320 can be provided tosubstantially mate with or be complementary to the male taper 310defined by the exterior of the first liner 304. As discussed above, thetapers 310, 320 can be substantially complementary and of anyappropriate angle. For example, the tapers 310, 320 can be formed toallow or form a Morse taper connection between the two tapers 310, 320.The Morse taper connection, or similar taper connection, can allow thefirst liner 304 to be substantially locked or fixed relative to theshell 302. The taper fixation can allow both axial and rotationalfixation of the first liner 304 relative to the shell 302.

The second liner 306 can also be similar to the second liner 206 of theacetabular assembly 200. The second liner 306 can be formed of amaterial that is softer than the first liner 304, such as a polymer. Thesecond liner 306 can also include an interior surface 330 forarticulation with a selected portion or component, such as a femoralhead implant 32 a, 32 b or a natural femoral head 34. An exteriorsurface 332 of the second liner 306 can also be provided to engage theshell 302 in a selected manner, such as in a contacting fit.

As illustrated in FIGS. 3A and 3B, a nipple or projection 305 can extendfrom the exterior wall 316 of the first liner 304 to be positionedrelative to an opening 333 in the shell 302. It will be understood thatthe projection 305 can be substantially cylindrical and need not engageany portion of the shell 302 once the first liner 304 is positionedwithin the shell 302. For example, the projection 305 can assist inaligning the first liner 304 with the shell 302 to ensure that therespective tapers 310, 320 are aligned for proper engagement andfixation of the first liner 304 within the shell 302. Once the firstliner 304 is engaged within the shell 302, the projection 305 need notengage or contact any portion of the shell 302. It will be understood,however, that the projection 305 can be configured to engage the shell302 in any appropriate manner at any appropriate time, such as afterinterconnection of the first liner 304 with the shell 302. It will befurther understood, that an alignment projection, such as the alignmentprojection 305, can be provided with any appropriate liner portion toassist in aligning the liner portion with the shell, such as the liners24 and 204.

With reference to FIG. 3C, substantially near an apex or an end of thesecond liner 306 can be a gripping or connecting region 334. Thegripping region 334 can include one or more flexible fingers 336 thatare hingedly connected with a portion of the exterior of the secondliner 306 via a hinge 338. The finger 336 can be allowed to flex, suchas via an opening or void 340. The void 340 can allow the fingers 336 todeflect radially relative to a central axis 341 of the second liner 306.As illustrated in FIGS. 3A and 3C, the fingers 336 can deflect as thesecond liner 306 is positioned within the shell 302 and the fingers 336can then rebound. A ledge or connecting portion 342 of the finger 336can engage a ledge or connecting ring 344 defined by the shell 302. Theconnecting ring 344 of the shell 302 can be positioned substantially inor near the apical hole 333 or apex of the shell 332. The apical hole333 can be provided for various other purposes, such as those discussedabove including implantation or positioning of the shell 302 relative tothe acetabulum 18.

The engagement of the finger 336 relative to the connecting member orring 344 can substantially axially hold the second liner 306 relative tothe shell 302. In addition, the second liner 306 can define fingers orprojections 350 and respective depressions 351 that can engage orcooperate with recesses 352 and respective projections 353 of the shell302 to substantially eliminate or reduce rotational movement of thesecond liner 306 relative to the shell 302. Thus, the second liner 306can be resist rotation relative to the shell 302.

With continuing reference to FIGS. 3A-3C, and additional reference toFIG. 3D, according to various embodiments, an acetabular assembly 300′can include an alternative shell 302′ and an alternative liner 306′. Thealternative liner 306′ can be substantially similar to the second liner306 except that a projection or nipple member 350 can extend from anexterior portion of the alternative liner 306′ which includes aconnecting portion 342′ to engage a connecting ring or ledge 344′. Theconnecting ledge 344′ can be a radially inwardly extending flange. Theprojecting portion 350 can be a substantially solid member. Insertion ofthe alternative liner 306′ into the shell 302′ can be accomplished bypressing the alternative liner 306′ into the shell 302′. By applying aforce into the alternative liner 306′, the connecting portion 342′ cancompress or deflect enough to pass the connecting ring 344′ to allow thealternative liner 306′ to be connected to the shell 302′. This can beassisted, at least in part, by an upper curved or slanted surface of theconnecting ring 344′. Accordingly, the projecting member 350 can be asubstantially solid member to fixedly engage the shell 302′.

With reference to FIG. 4A, an acetabular assembly 400, according tovarious embodiments, includes a shell 402 relative to which a firstliner 404 or a second liner 406 can be positioned. The shell 402 caninclude an exterior wall 408 operable to contact various portions, suchas an acetabulum of a patient. The exterior wall 408 can besubstantially spherical or curved. The shell 402 can also include aninterior wall 410. The interior wall 410 can be substantially sphericalor curved. The interior wall 410 can also include a distal or apicalhole 412 and a proximal or taper wall 414 that can define a selectedangle or taper. The apical hole 412, or a portion positioned relativethereto, can be provided to engage an apical nipple or engagementportion as discussed herein. The taper wall 414 can be provided toengage a complementary taper wall of the selected liner 404, 406 as alsodiscussed further herein. A rim 415 can define one or more anti-rotationdetents 416 and projections 417. The detents 416 can be spaced aroundthe rim 415 of the shell 402 to engage an anti-rotation system of aselected liner portion, as discussed further herein.

The first liner 404 can be provided to engage a portion of the interiorwall 410 of the shell 402. For example, a first exterior wall portion418 of the first liner 404 can engage a substantially hemispherical orsemispherical inner wall 410 of the shell 402. The first liner 404 canalso include an engagement or male taper 420 that is operable to engagethe internal taper region 414 of the shell 402. The taper walls canprovide a Morse or locking taper connection. For example, the angle ofthe taper wall 414, 420 can be about 1 degree to about 45 degrees.

The first liner 404 can be formed of a substantially rigid material,such as a ceramic material or metal, so that the male taper wall 420 isoperable to engage the interior taper wall 414 in a substantiallylocking manner. An alignment or engagement nipple 422 can also beprovided to assist in aligning of the first liner 404 relative to theshell 402 or for interconnecting the first liner 404 with the shell 402.It will be understood that the engagement of the taper wall 420 with theinterior taper wall 414 can assist in substantially holding the firstliner 404 relative to the shell 402 in both axial and rotational motion.The first liner 404 can also include an interior articulating wall 424operable to articulate with a selected member, such as a natural femoralhead 34 or a prosthetic femoral implant 32 a, 32 b, as discussed furtherherein.

With continuing reference to FIG. 4A and further reference to FIGS. 4Band 4C, the second liner 406 can also be positioned relative to theshell 402. The second liner 406 can be formed of an appropriatematerial, such as a moldable material including ultra-high molecularweight polyethylene or PEEK. The second liner 406 can include variousportions, such as a first outer wall portion 426 operable to engage thefirst interior wall portion 410 of the shell 402 and a second exteriorwall portion 428 operable to engage the interior taper wall 414 of theshell 402. In addition, a locking nipple or portion 430 can be providedto engage the apical hole 412 of the shell 402.

As specifically illustrated in FIG. 4C, the nipple 430 can include anengaging or extending portion 432 that is operable to pass a locking orshell ledge portion 434 to assist in holding or locking the second liner406 relative to the shell 402. The locking nipple 430 can assist inholding the second liner 406 against axial motion relative to the shell402. The second liner 406 can also include anti-rotation projections 440and associated detents 441, which can cooperate with the detents 416 andprojections 417 to assist in substantially eliminating or reducingrotational motion of the second liner 406 relative to the shell 402. Theshell 402 can also include an interior wall 442 that can articulate withvarious portions, such as a natural femoral head or a femoralprosthesis.

The second liner 406 can be provided substantially similar to the linersdiscussed above, such as the second liner 26 illustrated in FIG. 1A.According to various embodiments, however, the second exterior wallportion 428 of the second liner 406 can be provided relative to theinternal taper wall 414 of the shell 402 according to variousembodiments. For example, with reference to FIG. 4D, a liner 406 a,substantially similar to the second liner 406, can be provided relativeto the shell 402 including the internal taper wall 414 that includes asecond wall portion 428 a. The second wall portion 428 a can be providedsubstantially parallel to the interior taper wall 414 of the shell 402.Accordingly, an angle α between the interior taper wall 414 of the shell402 and the second wall portion 428 a of the liner 406 a can besubstantially zero. For example, in various embodiments the angle α canbe about zero degrees to about six degrees.

According to various embodiments, the second liner can be provided as asecond liner 406 b including a second exterior wall portion 428 b to bepositioned relative to the interior taper portion 414 of the shell 402.The second exterior wall portion 428 b can be provided with asubstantially non-complementary taper relative to the interior taper 414of the shell 402. For example, the second exterior wall portion 428 bcan be provided substantially parallel to a central axis 406′(illustrated in FIG. 4C). Accordingly, an angle β can be formed betweenthe interior taper wall 414 and the exterior wall 428 b. The angle β canbe about one degree to about fifteen degrees between the internal taperwall 414 and the second wall portion 428 b. Thus, the second wallportion 428, 428 a, 428 b can be provided with any appropriateconfiguration relative to the shell 402.

According to various embodiments, an acetabular assembly 500 includingfirst liner 502 and a second liner 504 that are both provided to beinserted or fixed to a single shell 506, is illustrated in FIG. 5A. Thefirst liner 502 can be formed of any appropriate material, such as arigid material, including a ceramic or other rigid materials, includingthose discussed above. The second liner 504 can be formed of a moreflexible material, such as an ultra-high molecular weight polyethylene,or other appropriate materials, including those discussed above.Regardless, both the first liner 502 and the second liner 504 can beinterconnected with the shell 506 in any appropriate manner, includingthose discussed further herein.

The first liner 502 can include an appropriate connection mechanism,such as a tapered wall, which can define a male taper 510. The maletaper wall 510 can interconnect or connect with a female taper wall 512,defined by the shell 506. The interconnection of the two tapers, 510,512, can include an appropriate taper connection, including thosediscussed above. For example, the two tapers, 510, 512 can be providedin an appropriate angle to provide a Morse taper fit between the firstliner 502 and the shell 506. In addition, the shell 506 can include anapical depression or bore 514, which can engage or receive a projectionor nipple 516 extending from an external wall 518 of the first liner502. The projection 516 can enter the apical depression 514 to assist inaligning the first liner 502. The first liner 502 can also include aninternal surface 520 for articulation with a selected portion, such as afemoral head implant or a natural femoral head.

The second liner 504 can also include an internal surface 530 that canarticulate with any appropriate portion, such as a femoral head or afemoral implant. The second liner 504 can also include a projection ornipple 530 that can include a ring or extended portion 532 that canengage a locking depression or area 534 defined within the apicaldepression 514 of the shell 506. The shell 506 can define an interiorsurface 538 and the apical depression 514 allows the locking portion 534to be positioned into a wall 539 of the shell 506 and outside of theinterior surface or interior 538 of the shell 506. In addition, thesecond liner 504 can define an anti-rotation system includingprojections 540 and depressions 542 that can engage respectivedepressions 546 and projections 548 of the shell 506. Accordingly, thesecond liner 504 can resist rotation relative to the shell 506. Thefixing system can be used to axially hold the second liner 504 withinthe shell 506.

As particularly illustrated in FIG. 5B, the second liner 504 can bepositioned within the shell 506 so that the locking projection 532 ispositioned within the locking depression 534 of the shell 506. Thelocking depression 534 of the shell 506 has a shell locking projection550 that projects from a wall of the apical depression 514. The secondliner 504 can be pressed into the shell 506 to allow the linerprojection 532 to deflect as it passes over the shell projection 550 andthen relax into the depression 534 to hold the second liner 504 relativeto the shell 506.

The shell 506 can also define a thread 560 within the apical depression514. The thread 560 can be defined in the apical depression 514 betweenthe locking depression 534 and an exterior 562 of the shell 506. Theshell 506 can define a bore in the apical depression 514 or it caninclude an optional thin wall 564 to cover or block the apicaldepression 514. The thin wall 564 can be provided for various purposes,such as eliminating or reducing particle migration out of the interiorof the shell 506.

The wall of the shell 506 can include a first thickness 570 near a rim572 of the shell 506 and a second thickness 574 near the apicaldepression 514. The second thickness 574 can be greater than the firstthickness 570. The amount of the second thickness 574 can allow for thecreation of the threads 560 near the apical depression 534 within theshell 506.

With continuing reference to FIG. 5B and additional reference to FIG.5C, the threads 560 can be used to connect or interlock withcomplimentary threads 580 of an insertion instrument 582. The insertioninstrument 582 can be any appropriate insertion instrument, such as theacetabular cup insertion instrument, sold by Biomet, Inc., having aplace of business in Warsaw, Ind. The insertion instrument 582 cangenerally include a shaft 584 and an impaction head 586. It is generallyunderstood the impaction tool 582 can readily engage the threads 560 ofthe shell 506 and an appropriate instrument, such as an impactionhammer, can contact the impaction head 586 to impact the shell 506 intothe anatomy 1000 (FIG. 7). The threads 560 defined in the shell 506 canallow for a secure attachment of the impaction tool 586 to the shell 506during implantation. After implantation, the impaction tool 582 can beefficiently unthreaded from the threads 560 defined by the shell 506 toremove the impaction tool 586 and allow inner connection of either thefirst liner 502 or the second liner 504.

According to various embodiments, an acetabular assembly 600 can includea first liner 602 and a second liner 604 that can both be provided tointerconnect with a single shell 606, as illustrated in FIG. 6A. Thefirst liner 602 can be a rigid liner, similar to the rigid linersdiscussed above. In addition, the second liner 604 can be a more suppleor flexible liner, similar to those discussed above.

The first liner 602 can define a male taper wall 610 that can engage afemale taper wall 612 in an appropriate manner, such as with a Morsetaper locking connection or other appropriate connection as discussedabove. The first liner 602 can also include an external wall 614 fromwhich a nipple or aligning projection 616 can extend. The aligningprojection 616 can engage or cooperate with an apical depression or bore618 defined by a wall of the shell 606. As discussed above, the aligningprojection 616 can be positioned within the apical depression 618 toassist in aligning the first liner 602 to allow for appropriateinterconnection of the male taper 610 and the female taper 612. Thefirst liner 602 can also include an interior surface 620 that can allowfor articulation of an appropriate portion, such as a femoral headimplant or a femoral head.

The second liner 604 can also include an interior surface 622 forarticulation with a femoral head implant or a femoral head. The secondliner 604 can also include an exterior surface 624 from which a lockingor holding projection 626 can extend. The locking projection 626 caninclude a locking portion 628 that can engage a locking depression 630defined within the apical depression 618. The shell 606 can define orinclude an interior that is defined by an interior wall 632. The apicaldepression 618 can allow for the locking depression 630 to be positionedoutside of the interior or the interior wall 632 of the shell 606. Thesecond liner 604 can also include an anti-rotation mechanism or a systemincluding anti-rotation projections 638 and respective depressions 640.The projections and depressions 638, 640 of the second liner 604 cancooperate with respective depressions 642 and projections 644 of theshell 606 to allow for the second liner 604 to resist rotation relativeto the shell 606. The locking portion 628 holds the second liner 604axially relative to the shell 606.

With continuing reference to FIG. 6A and additional reference to FIG.6B, the shell 606 can also include or define an implantation depression650. The implantation depression 650 can be an angular ring ordepression defined within the inner wall 632 of the shell 606. Inaddition, the implantation depression 650 can be defined in an area thatfurther defines the female taper 612. The implantation depression 650,however, can be provided to allow for engagement or cooperation with animplantation instrument 652. The implantation instrument can be anyappropriate implantation instrument, such as the inserter instrumentused with the Regenerex® revision cup system sold by Biomet, Inc.,having a place of business in Warsaw, Ind. Briefly, the implantation orimpaction instrument 652 could include a shaft 654 having an impactionhead 656. The impaction instrument 652 is diagrammatically illustratedmerely for exemplary purposes and may be augmented for particularimplantation procedures or cups. Nevertheless, the impaction orimplantation instrument 652 could include projecting or engaging arms658 that can move from a retracted position 658 a, (shown in phantom) toan extended position to engage the implantation Depression 650 as theimpaction head 656 is moved in the direction of arrow 659 toward theapical depression 618. An interior wall engaging head 660 can also beprovided to align the impaction instrument 652 and engage the interiorsurface 632 of the shell 606. Nevertheless, the arm 658 can engage theimplantation depression 650 to allow for an appropriate implantation orimpaction force to be provided to the shell 606 as it is implanted intothe anatomy 1000 (FIG. 7).

A wall, such as a thin wall 670, can also be provided near the apicaldepression 618. The apical depression 618 can, therefore, be completelyclosed to an exterior of the shell 606. As discussed above, the thinwall can assist in eliminating or reducing particle migration out of theinterior of the shell 606.

With additional reference to FIG. 6C, the second liner 604 can bepositioned within the shell 606 by pressing the locking portion 628 pasta shell locking projection 672 into the shell locking or receivingdepression 630. As discussed above, the thin wall 670 can define anexterior to the apical depression 618 defined by the shell 606. Thesecond liner 604 can be substantially held within the shell 606 with theinteraction or cooperation of the receiving groove 630 defined by theshell 606 outside of the interior 632 and the holding projection 628defined by the second liner 604. The implantation depression 650 doesnot engage or hold the second liner 604 within the shell 606.Additionally, the implantation depression 650 does not cooperate withthe first liner 602 to hold the first liner 602 within the shell 606.

It will be understood that the acetabular assemblies, according tovarious embodiments, can be provided for use by a user such as asurgeon. In addition, the various assemblies can be altered for variouspurposes. For example, an acetabular assembly can include both the liner306 and the liner 206 with the liners 304 and 204, which may besubstantially similar. In addition, multiple shells may be providedincluding the characteristics of two or more shells 22, 202, 302, 302′,402, 506 and 606. Therefore, it will be understood that an assembly canbe provided for any appropriate purpose.

Further, the various liners and shells can be formed of any selected orappropriate materials, as is understood by one skilled in the art.Therefore, although exemplary materials are provided for both a hard orrigid liner and a soft or flexible liner, other appropriate materialscan be used.

An acetabular assembly, according to various embodiments including thosediscussed above, can be implanted relative to the acetabulum 18 of ananatomy 1000. With reference to FIG. 7, the anatomy 1000 can include apelvis 1002 which can define the acetabulum 18. Physicallyinterconnected with the pelvis 1002 can be a spinal column 1004 of apatient having the anatomy 1000. It will be understood that theacetabular assemblies illustrated above can be implanted in anappropriate manner. According to various embodiments, however, theacetabular assembly 20 can be implanted as discussed herein. It will beunderstood that the other acetabular assemblies can be implanted in asimilar manner with variations for the specifics of the liners andshells discussed above. In addition, the liners, according to variousembodiments, can include constraining liners, such as those that includehigh walls and other features.

Exemplary liners or implant systems include Ringloc® Liners sold byBiomet, Inc. of Warsaw, Ind., USA.

As illustrated in FIG. 7, the shell 22 can be positioned within theacetabulum 18 in any appropriate manner. One skilled in the art willunderstand that the acetabulum 18 can be prepared in any appropriatemanner, for example via reaming, cement placement, or fastenerplacement. The shell 22 can be fixed to the acetabulum 18 in anyappropriate manner. For example, a cementless fixation can be used, acement fixation, a screw or member fixation or any other appropriatefixation. For example, Ringloc® acetabular cup systems can be implantedwith cement, without cement, and with or without screws or otherfixation members.

During an operative procedure, once the surgeon has positioned the shell22 within the acetabulum or even prior to the positioning of the shell22, but after the beginning of a procedure, a surgeon may determine thata different type of prosthesis may be necessary or that damage to theanatomy is greater based upon visual inspection as opposed to othertypes of inspection. Therefore, once the procedure has begun either thefirst liner 24, which can be a substantially hard or rigid liner, can bepositioned within the shell 22 or the second liner 26, which can be asofter liner, can be positioned within the shell 22. The selection ofeither of the liners 24, 26 for positioning within the shell 22 canallow for other options in a procedure, such as positioning of a femoralhead implant 32 a, 32 b or maintaining a natural femur head 34 forarticulation. The head implant 32 a, 32 b can include various materials,such a metal, ceramic, or other appropriate materials. Also, thediameter or size of the implant 32 a, 32 b can depend on materials,patient size, etc. A kit of different sizes can be provided, ifselected. It can also be selected to have the head implant 32 a, 32 b tobe of the same material as the liner, according to various embodiments.

For example, during a preoperative planning stage, a surgeon maydetermine that a femoral implant 32 may be necessary and the surgeon maydesire to use the first liner 24, which is substantially rigid. Thesurgeon may, however, desire to have an option of maintaining thenatural femur 34, allowing it to articulate with the softer second liner26. Therefore, the acetabular assembly 20 may be provided to allow thesurgeon such an option. Once the procedure has begun, and based onvisual inspection, the surgeon may determine that the femoral implant 32is necessary and prepare the femur for the implantation of the implant32, and select the first liner 24 for positioning into the shell 22. Thesurgeon may, alternatively, determine that the natural femoral head 34is salvageable and elect to position the second liner 26 within theshell 22 for articulation with the natural femoral head 34. Therefore,the acetabular assembly 20 can allow for the connection of either thefirst liner 24 or the second liner 26 during an operative procedure.

Once the selection of the liner is made, the liner can be positionedwithin the shell 22. For example, if the first liner 24 is selected tobe used, the interconnection of the male taper 44 of the first liner 24and the female taper 40 of the shell 22 can be used to interconnect thefirst liner 24 with the shell 22. Alternatively, the connecting member28 can be used to engage the connecting first groove 72 of the shell 22if the second liner 26 is provided.

As discussed above, the provision of the two connection portions, thefemale/male taper connection or the connecting member connection in therespective grooves 72, 74, positions the different connecting portionsat a distance from one another. Therefore, the first connecting systemwill not interfere with the second connecting system of the acetabularassembly 20.

In addition, it will be understood that any appropriate instruments canbe used to insert either of the selected liners 24, 26 and further thatthe procedure for the implantation can proceed to any appropriate planselected by a surgeon. The selection of the liners relative to a singleshell, however, can allow for selectability during an operativeprocedure allowing for efficiency in the procedure and selection by thesurgeon resulting in a selected outcome for the patient.

According to various embodiments of the acetabular assembly, the liners,such as the liners 24, 26 of the acetabular assembly 20, can each beconnected with a connection portion (i.e. the taper connection 40, 44 orthe connecting member 28 and grooves 72, 74). Each of the connectionportions interconnecting the respective liners 24, 26 with the shell 22can be engaged completely or substantially independently of the otherdepending upon the liner positioned within the shell 22. Therefore, whenthe female taper 40 is engaged with the male taper 44, the connectingmember 28 need not engage the first groove 72 defined by the shell 22.

According to various other embodiments, such as the acetabularassemblies 200, 300, the various liners can separately and distinctlyengage one of the two or more connecting portions or areas provided withthe shell 202, 302. According to various embodiments, the first liner204 can include the button 205 that engages the apical opening in theshell 202, but does not engage the apical opening 220 for holding thefirst liner 204 relative to the shell 202. Similarly, the first liner304 can include the nipple 305 that can engage the apical opening 333 inthe shell 302. The guide buttons 205, 305 can assist in guiding theliners 204, 304 into the shell 202, 302. This can assist in assuring anappropriate alignment of the taper connections between the liners 204,304 and the shells 202, 302. In addition, the second liners 206, 306 caninclude complementary exterior shapes to engage, substantially flushly,the interior of the respective shells 202, 302 but do not engage thetapers in a fixed manner. As discussed above, the second liners 206, 306can be formed of a material that is generally soft or flexible.Therefore, the tapers defined by the respective shells 202, 302 do notneed to securely engage or fixedly engage the liners 206, 306 within theshells 202, 302. The second connecting portion defined within the apicalhole of the shells 202, 302 holds the liners 206, 306 axially within theshells 202, 302.

In the alternative, however, the liners, according to variousembodiments, can engage more than one connecting portion relative to theshell, according to various embodiments. For example, with reference toFIGS. 1B and 1C, the first liner 24 can include both the male taper 44and a groove 74 a, shown in phantom, to engage the connecting member 78,similar to the connection in FIG. 1C. In this way, the first liner 24can engage the shell 22 at two positions. Similarly, as discussed abovethe second liner 26 can also include the button or projection 89 thatcan be positioned in or engage the female taper 42. Thus, the secondliner 26 can also engage the shell 22 both with the locking member 78and in the female taper 42.

Similarly, liners according to various embodiments can engage shells,according to various embodiments, at more than one connection location.As a further example, the first liner 204 can include both the maletaper 272 and a button 205 that includes a groove 205 a to engage theconnection member 208. Similarly, the second liner 206 can include amale taper 207 that can engage or connect with the female taper 216 ofthe shell 202. Thus, liners of various embodiments can engage shells ofvarious embodiments at two or more portions or locations to connect theliners to the shells.

The first connection portion and the second connection portion can bepositioned, as discussed above, at selected distances from one anotherdefined by a shell, such as the shell 22. As discussed herein, a firstconnection portion, including the female taper 40 can be positioned atan apex or proximal position (as defined by the implantation position ofthe shell 22). The second connection portion, including the first groove72, is positioned substantially near or at the rim 70 or distal positionof the shell 22.

Returning reference to FIG. 1 B, the first connection portion 72 ispositioned at least above a plane or line A that can divide the shell 22in half by height between the rim 70 and a an apex point. It will beunderstood that the position of the first groove 72 may be alteredrelative to the middle line A, but generally is positioned above themiddle line relative to the shell 22. In addition, it will be understoodthat a similar line may be positioned substantially one third towardsthe rim 70 or towards the apex point 41 of the shell 22 where the femaletaper 40 is positioned below or towards the apex point 41 and the firstgroove 72 is positioned towards the rim 70, still substantiallyseparated by the separating line A. It will be further understood thatthe various embodiments include similar positions of the first andsecond connection portions. A second line or plane A1 can define aproximal extent of the cavity or internal surface of the shell,according to various embodiments. The internal surface can extend fromthe rim to the line A1 to receive or engage a liner, according tovarious embodiments.

Therefore, the first and second connection portions, for example,including the female taper 40 and the first groove 72, can be positionedsubstantially separately and discreetly as defined by the shell 22, orany shell according to various embodiments. According to variousembodiments, such as the shells 202 and 302, the female taper positionedsubstantially near the rims can be positioned with a similar separationline separating them from the second connection portion positioned nearor at the apex or a proximal portion of the shells 202, 302. Accordingto various embodiments, at least one connection portion can bepositioned outside of the cavity, either beyond line A1 (such as withina wall of the shell) or beyond the rim of the shell.

As a further example, the shell 22 can define the internal surface 38that extends from, at, or near the rim 70 to an apex internal surface,such as the part of the internal surface 38 that defies the thickness54, 56. Thus, the first groove 72 can be positioned within the internalsurface or cavity 38 of the shell 22. The apical opening defining thefemale taper 40, however, can be defined by the shell 22 having thethickness 54, 56. The shell wall 22 a having the thickness 54, 56 candefine the female taper 40 outside of the internal surface 38. In otherwords, the female taper 40 is defined between the internal surface 38and an exterior surface 39 and not within a cavity or void defined bythe internal surface 38.

According to various embodiments, one or both of the liners can engageboth of the connection portions simultaneously or during or afterimplantation. Thus, one skilled in the art will understand that whilediscussion herein may be focused primarily upon connecting a liner withonly one connection portion, that a liner can also be connected with twoor more connection portions at the same time. The multiple connectionscan be provided for various reasons, such as securing the liner at morethan one location, guiding the liner into an implantation position,reduction in manufacturing processes, etc.

According to various embodiments, an implant assembly for an anatomyincludes a shell operable to be implanted into the anatomy, the shellincluding a first connection portion positioned at a first locationrelative to the shell and a second connection portion positioned at asecond location remote from the first location. A first liner includinga first liner connection portion operable to connectingly engage onlythe first connection portion of the shell and a second liner including asecond liner connection portion operable to connect only to the secondconnection portion defined by the shell. The shell and the first linerand the second liner include complementary configurations such that thefirst connection portion is positionable near only the first linerconnection and the second connection portion is positionable near onlythe second liner connection portion. Also, at least one of the firstconnection portions or the second connection portions defined by theshell can be defined within or by a wall of the shell such that it isnot within a cavity or defined by an internal surface of the shell. Theshell includes a wall that has an internal surface that defines aconcave surface having an apex wherein the first connection portion isdefined in the wall defining the concave surface. The first connectionportion includes a taper wall defining a bore through the wall at ornear the apex. The second connection portion includes a groove definedwithin the concave surface at or near the rim.

According to various embodiments, an implant assembly for positioning inan anatomy can include: a shell having a wall defining a distal rim anda proximal apex portion; a first connection portion defined by the shellnear the distal rim; and a second connection portion defined by the wallof the shell near the proximal apex portion. The first connectionportion and the second connection portion are separated completely by atransverse division line defined by the shell. A first liner defines afirst liner distal rim and includes a first liner connection operable toengage the first connection portion near the first liner distal rim. Asecond liner defines a second liner proximal apex and includes a secondliner connection operable to engage the second connection portion nearthe second liner proximal apex. The shell further includes ananti-rotation mechanism including at least one depression, functioningto receive a liner anti-rotation mechanism including at least oneprojection. The first liner defines the anti-rotation projection andfurther defines a groove forming at least a portion of the first linerconnection, and further includes a connecting member operable tointerconnect to the first connection portion and the first linerconnection portion. The second liner defines at least a flexible fingerforming at least a portion of the second liner connection wherein thesecond connection portion includes a depression from an internal surfacedefined by the shell to receive at least a portion of the finger. Thefirst connection portion includes a taper or a groove and the secondconnection portion includes a taper, a groove, or a projection. Thetransverse division line is defined at least between a distal third ofthe shell and a proximal third of the shell. The first liner can beformed of a first material less rigid than a second material from whichthe second liner is formed. The first connection portion includes agroove defined by the shell and the first liner connection includes agroove defined by an exterior wall of the first liner, wherein aconnecting member is operable to interconnect the first liner and theshell via interconnection with the first groove defined by the shell andthe second groove defined by the first liner. The second liner defines amale taper which forms the second liner connection, and the secondconnection portion of the shell includes a female taper, wherein theinterconnection of the male taper and the female taper locks the secondliner to the shell. The shell includes a plurality of shells, whereineach of the plurality of the shells includes the second connectionportion, each defining a female taper, wherein each female taper definedby each of the plurality of the shells includes a different height. Theprosthesis can further include a femoral implant including a femoralhead having a surface operable to move relative to at least one of thefirst liner or the second liner, wherein the shell is an acetabularshell operable to be implanted into an acetabulum of the anatomy.

According to various embodiments, a method of implanting a prosthesisassembly into an anatomy can include providing a first shell member,providing a first connection portion positioned at a first positionrelative to the shell, providing a second connection portion positionedat a second position relative to the shell, and providing the firstposition separated by a dividing line defined by the first shell fromthe second position. A first liner, including a first liner connection,operable to connect with only the first connection portion and a secondliner, includes a second liner connection, operable to connect with onlythe second connection portion may also be provided. The method canfurther include selecting only one of the first liner or the secondliner, and connecting the selected first liner or the second liner withthe respective connection portion of the first shell member. The methodcan also include aligning the first or second liner relative to theshell member in order to align the respective first or second connectionportion with the first liner connection or the second liner connection,wherein aligning includes at least positioning a positioning buttonwithin a bore defined by the first shell member. The method can furtherinclude implanting the first shell member into the anatomy, prior toconnecting the selected first liner or the second liner with therespective connection portion. In addition, the method can includeimplanting the first shell member into the anatomy prior to selectingonly one of the first liner or the second liner for connection to thefirst shell member. The method can also include beginning an operativeprocedure on the anatomy including visualizing a selected portion of theanatomy, and selecting only one of the first liner or the second linerbased upon the visualization of the anatomy after the beginning of theoperation. Positioning the first shell member in the anatomy afterselecting only one of the first liner or the second liner, andconnecting the first liner or the second liner to the first shell memberafter the first shell member has been positioned in the anatomy, mayalso be performed. Likewise, the method can include resecting a portionof the femur of the anatomy and implanting a femoral implant into theanatomy, wherein selecting only one of the first liner or the secondliner includes selecting the first liner or the second liner to form anarticulation with the femoral implant. An operating theater can beprovided, where an operation is occurring, with at least the first shellmember, the first liner, and the second liner; wherein selecting onlythe first liner or the second liner includes selecting only the firstliner or the second liner for connection with the first shell member;and wherein selecting only the first liner or the second liner occursduring the operative procedure. In further detail, providing a firstconnection portion can include providing at least a depression in thefirst shell member and providing a groove in an interior wall of thedepression provided in the first shell member; wherein the depressionextends from a concave surface defined by the first shell member;wherein providing the first liner connection portion includes providingan extending portion extending from the first liner and a grooveprovided in the extending portion.

These teachings are merely exemplary in nature, thus, variations that donot depart from the gist thereof are intended to be within the scope ofthe teachings. Such variations are not to be regarded as a departurefrom the spirit and scope of these teachings.

What is claimed:
 1. An acetabular implant assembly for positioning in ananatomy, comprising: a shell with a shell wall extending from a proximalapex portion to a distal rim, the distal rim defining a first passageoperable to receive a liner, wherein the shell has an internal wallsurface defining an internal void and an external wall surface; a firstconnection portion formed in the shell by the internal wall near thedistal rim; a second connection portion formed in a bore defined by abore wall that extends through the shell wall from the internal wallsurface to the external wall surface near the proximal apex portion; acurved wall portion defined by the shell wall extending between thefirst connection portion and the second connection portion; wherein thedistal rim of the shell defines a rim plane and a central line extendingsubstantially normal to the rim plane extends through the proximal apexportion; wherein the first connection portion and the second connectionportion are separated completely by a division line transverse to thecentral line defined in the shell; a first liner having a first linerdistal rim, a first liner proximal apex, a first liner connectionportion formed by an exterior of the first liner configured to engagethe first connection portion near the first liner distal rim, and analignment nipple disposed at the first liner proximal apex that isaligned with and received by the bore extending through the shell wall,the alignment nipple having a smooth exterior such that the alignmentnipple is not retained by the second connection portion formed in thebore; and a second liner defining a second liner distal rim, a secondliner proximal apex, and a second liner connection portion configured toengage the second connection portion near the second liner proximalapex, wherein the second liner connection portion includes a lockingnipple extending along a nipple axis from an outer surface of the secondliner and an extending portion that extends substantially transverse tothe nipple axis, wherein the extending portion is configured to pass,engage, and be retained by the second connection portion, and whereinthe first liner is formed of a first material that is more rigid than asecond material that forms the second liner.
 2. The implant assembly ofclaim 1, wherein the first connection portion includes a taper and thesecond connection portion includes a groove; wherein the firstconnection portion and the second connection portion are configured tobe engaged without rotation.
 3. The implant assembly of claim 1, whereinthe division line is defined at least between a distal third of theshell and a proximal third of the shell.
 4. The implant assembly ofclaim 1, further comprising: a femoral implant including a femoral headhaving a surface operable to move relative to at least one of the firstliner or the second liner.
 5. The implant assembly of claim 1, whereinthe extending portion includes a first wall that extends substantiallyperpendicular to the nipple axis and a second wall that is angledrelative to the nipple axis.
 6. The implant assembly of claim 5, whereinthe second connection portion includes a ledge extending into the borefrom the bore wall to engage the extending portion.